A Greenhouse is a facility that is set up or conditioned to give favorable environmental conditions and protections to crops, for the purpose of curbing activities of pests, diseases and unfavorable weather conditions. Greenhouse farming is the unique farm practice of growing crops within sheltered structures covered by a transparent, or partially transparent, material. The main purpose of greenhouse farming is to provide preferred growing conditions and to protect crops from harsh weather, pests and diseases, through a controlled environment.
The idea of a controlled environment is one of the many farm management innovations for better agricultural practices and output. Weather, climate change, pests and diseases have been limiting agricultural productivity, thereby increasing the chances and occurrences of food insecurity. To have a food secure society, innovations must happen, and a Greenhouse farm is one of the great innovations to crop production.
Common Types of Greenhouse
- Screen Greenhouse: This greenhouse is made of covered screening material that prevents or curbs pests and adverse weather conditions. It is common in the tropics, arid and semi-arid regions.
- Shade Greenhouse: The shade type of greenhouse is commonly a woven fabric or other similar material with allowance passages for natural sunlight, moisture or humidity and air.
- Glass Greenhouse: This structure is carved out of glass, so that it is transparent enough without allowing entrance of pests and weather elements such as humidity or moisture.
- Crop top Greenhouse: This type of greenhouse is likened to a roof top with no walls or fences. It mostly reduces direct supply of rainfall, frost, sunlight.
Strengths of Greenhouse Farming
- Control: Greenhouse being a controlled environment, the farmer can control external elements or factors, basis the level of effect they would have on crops. Temperature, humidity, light etc. can be controlled to fit requirement. Farmers can also afford to ignore natural season term and create their own season, growing crops in and out of season and for shorter periods.
- Pest Management: Greenhouse farming helps to keep plants away from their common pests and diseases. Pests that are dependent on the natural environment and weather where certain plants are usually grown may find it difficult to locate them or breed in the greenhouse.
- Specialty: Greenhouse farming is specific for farmers who specialize in certain category of plants which usually require less root and cover spaces to thrive. Vegetable plants, short-breed faster-fruiting fruits, floricultural plants, and transplants are best suited for greenhouses.
Within the strengths of greenhouse farming lie some weaknesses. Controlling elements of weather and climate can be challenging and require high level of expertise. The greenhouse is limited to accommodating only plants with small space requirement. The closed nature of a greenhouse requires a different management technique in comparation with open farming.
Pests and diseases if not adequately controlled can go out of hand and lead to worse destruction in a greenhouse than it would in the open field. Adequate irrigation is needed to supply the plants in a greenhouse, mostly via sprinklers or drip irrigation system. High intensity of heat and light may be needed, especially when producing warm season vegetable plants during winter. All of these require high technique and extra funding, so much that if practiced on a small scale with low turnover, the output and profitability may not match the input.
Opportunities in Greenhouse Farming
- Increased Output: Greenhouse when properly managed, contribute immensely to success of plants and increase output of farmers. The level of output is proportional to the farmer’s profitability. Profitable farmers are happier and can invest more in food production after each harvest season.
- Food Security: Considering the increasing rise in fear of food insecurity due to environmental hazards caused by climate change, greenhouse farming is an effective tool for food security. Factors such as global warming and resulting climate change would have lesser effect on food produced in greenhouses.
- Economic Growth: Countries who invest in greenhouse production have more food to consume and supply other countries. This improves the trade and commerce sector of such countries and has a direct positive impact on their GDP. They are also able to grow more crops of exotic species, eventually localizing them into indigenous species.
- Job and Employment: Emergence and increase in need for greenhouses has triggered new employment openings. Production and sale of greenhouse materials, technical expertise of greenhouse activities, creation of compatible seed breeds or variants, labor on greenhouse, supply chain of farm produce and value-added products, research and many more are employment opportunities related to greenhouse farming.
Threats to Greenhouse farming
- Public Health Threat: Public health specialists and institutes at local, regional and international level all insist that greenhouse emissions create air pollution which are hazardous to public health and the environment. Greenhouse gas emissions also known as GHGs are said to be the basic cause of climate change, which usually result in hotter and more lengthy heat waves, threatening the health of vulnerable people. GHGs lead to increased ground-level ozone pollution that may cause asthma and other respiratory diseases, among other health challenges.
- Cost: Greenhouse farming can be costly and expensive to build, such that many small scale and rural farmers cannot afford them. This will in turn affect the source of income of such small farmers as greenhouse farmers take the larger chunk of the market. This may in turn lead to economic problems through artificial scarcity, increase in food price, and poverty.
- Other Threats: Greenhouse is like a baby project and therefore needs constant maintenance, monitoring, technicality, and care. Electricity consumption and reliance is very high in greenhouse farming and this makes it not a great fit in developing or underdeveloped country where there is unstable, interrupted power supply, meaning they have to go through extreme conditions and cost to make water and electricity available. In environments where the power supply is constant, greenhouse farmers may accumulate high water and light bills. For people who love nature and ambience of farms and open field, the greenhouse may reduce or overshadow such natural aesthetic view.